HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH RSS TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Full Text (PDF) All Versions of this Article: jnumed.107.042085v1 48/8/1320    most recent Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in JNM Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by van Waarde, A. Articles by Elsinga, P. H. Search for Related Content PubMed PubMed Citation Articles by van Waarde, A. Articles by Elsinga, P. H.

Rapid Reduction of ₁-Receptor Binding and ¹⁸F-FDG Uptake in Rat Gliomas After In Vivo Treatment with Doxorubicin

¹ Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; ² Division of Tracer Kinetics, Advanced Science Research Center, Central Institute of Radioisotopes Science, Kanazawa University, Kanazawa, Japan; and ³ Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan

Correspondence: For correspondence contact: Aren van Waarde, PhD, Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713GZ Groningen, The Netherlands. E-mail: a.van.waarde{at}pet.umcg.nl

-Receptors are strongly overexpressed in most rodent and human tumors and are proliferation markers. To evaluate the potential of a radiolabeled ₁-ligand for therapy monitoring, we compared early changes of ¹¹C-1-(3,4-dimethoxyphenethyl)-4-(3-phenylpropyl)piperazine (¹¹C-SA4503) binding and ¹⁸F-FDG uptake in gliomas after in vivo chemotherapy. Methods: C6 cells (2.5 x 10⁶) were subcutaneously injected into the right shoulder of male Wistar rats. After 7 d, the tumor volume was 0.60 ± 0.08 cm³. Animals then received either saline or doxorubicin (8 mg/kg, intraperitoneally). One control and 1 treated rat were imaged simultaneously, 24 or 48 h after treatment, under pentobarbital anesthesia. Rodents (n = 20) were scanned first with ¹¹C-SA4503 (25 MBq, intravenously) followed more than 100 min afterward by ¹⁸F-FDG (20 MBq, intravenously), using a dedicated small-animal PET camera (60-min protocol, tumors in the field of view). Tumor homogenates were prepared and subjected to -receptor assays. The biodistribution of ¹⁸F-FDG was assessed. Results: Tumors appeared 4–5 d after inoculation and grew exponentially. No significant reduction of tumor growth was visible within 48 h after doxorubicin treatment. Both PET tracers visualized the tumors and showed reduced uptake after chemotherapy (¹¹C-SA4503: 26.5% ± 6.5% at 24 h, 26.5% ± 7.5% at 48 h; ¹⁸F-FDG: 22.6% ± 3.2% at 24 h, 27.4% ± 3.2% at 48 h; ex vivo ¹⁸F-FDG: 22.4% ± 5.4% at 24 h, 31.7% ± 12.7% at 48 h). ₁-Receptor density in treated tumors was also reduced (from 172 ± 35 to 125 ± 28 fmol/mg of protein). Conclusion: Both ¹¹C-SA4503 binding and ¹⁸F-FDG uptake declined in gliomas after chemotherapy. Decreased binding of ¹¹C-SA4503 corresponded to a loss of ₁-receptors from the tumors. Changes in tracer uptake preceded the morphologic changes by at least 48 h.

Key Words: ¹¹C-SA4503 • chemotherapy • tumor • doxorubicin • microPET

COPYRIGHT © 2007 by the Society of Nuclear Medicine, Inc.

Related articles in JNM:

This Month in JNM

JNM 2007 48: 11a-12a. [Full Text]  

This article has been cited by other articles:

				C. Murayama, N. Harada, T. Kakiuchi, D. Fukumoto, A. Kamijo, A. T. Kawaguchi, and H. Tsukada Evaluation of D-18F-FMT, 18F-FDG, L-11C-MET, and 18F-FLT for Monitoring the Response of Tumors to Radiotherapy in Mice J. Nucl. Med., February 1, 2009; 50(2): 290 - 295. [Abstract] [Full Text] [PDF]